While power generated from wind and solar sources is growing in modest amounts, global nuclear generation capacity has fallen from last year's record of 375.5 gigawatts to 365.5 gigawatts in 2011. Certainly, 10 gigawatts is a small drop in absolute terms as well as percentage-wise, but it is a 10-gigawatt decline. For comparison, 10 gigawatts is half of the global solar market or about one-quarter of the peak California ISO load.

It's probably too early to call the declining reliance on nuclear power a trend, but high costs, recent disasters, and government moratoriums on nuclear are creating a difficult environment in which to design and build new nuclear. Additionally, an aging fleet of reactors, which are in some cases already past their expiration date, are going to require de-commissioning or massive overhauls. And a general slowdown in electricity usage, along with low natural gas prices will not encourage nuclear build-out. Just 10 of Japan's 54 nuclear reactors are connected to the grid; China halted construction on 25 reactors right after the Fukushima explosions; and Germany and Switzerland announced their intention to phase out nuclear plants following the disaster.

Worldwatch Institute's Vital Signs Online (VSO) report indicates that "nuclear's share of world commercial primary energy usage fell to around five percent in 2010, having peaked at about six percent in 2001 and 2002." Just four countries -- the Czech Republic, Romania, Slovakia, and the United Kingdom -- actually increased their share of nuclear power in an appreciable way between 2009 and 2010.

The trend shows signs of continuing. According to the report, "Although 16 new reactors began construction in 2010, the highest number in over two decades, that number fell to just two in 2011, with India and Pakistan each starting construction on a plant."

The total number of reactors in operation around the world has declined from 441 at the beginning of the year to 433.

China and the U.S. are the exception to the decline in global nuclear electricity generation. China was responsible for 10 of the 16 reactor construction starts in 2010 and began to install nearly 10 gigawatts of capacity in 2010, representing 62 percent of capacity construction worldwide. China currently has 27 reactors and 27 gigawatts of capacity under construction, according to the report.

The United States doesn't seem to be retreating from the nuclear power cause either. In 2010, the Obama administration approved $8.3 billion in loan guarantees for the construction of nuclear reactors, and recent budget proposals have raised that figure by an additional $36 billion.

Further highlights from the report:

China, India, Iran, Pakistan, Russia, and South Korea have contributed around 5 gigawatts of new installed capacity since the beginning of 2010.

During this same period, nearly 11.5 gigawatts of installed capacity has been shut down in France, Germany, Japan, and the United Kingdom.

Germany alone has taken around 8 gigawatts of installed nuclear capacity offline this year.

Currently, 65 reactors are under construction around the world; however, 20 of these have been under construction for more than 20 years.

Construction of the first nuclear power plant to be built in France in 15 years has been delayed until 2016, and its projected cost has grown from approximately $4.4 billion to approximately $8 billion.

The average age of decommissioned reactors worldwide has risen to 23 years.

In 2009, the U.S. Nuclear Regulatory Commission received 26 nuclear reactor permit applications, but only four of those sites have plans for construction.

Eric Wesoff is Editor-at-Large at Greentech Media. Prior to joining GTM, Eric Wesoff founded Sage Marketing Partners in 2000 to provide sales and marketing-consulting services to venture-capital firms and their portfolio companies in the alternative energy and telecommunications sectors. Mr. Wesoff has become a well-known, respected authority and speaker in these fields.

His expertise covers solar power, fuel cells, biofuels and advanced batteries. His strengths are in market research and analysis, business development and due diligence for investors. He frequently consults for energy startups and Silicon Valley's premier venture capitalists.